Carbon dioxide-based chromatography systems of today (e.g., supercritical fluid chromatography or SFC) require refrigeration at their inlet pumps to ensure that the carbon dioxide (CO2) is in liquid phase so that the pump can meter the CO2. Conventional methods use high-cost refrigeration units to cool the CO2 prior to pumping in HPLC (High Performance Liquid Chromatography) applications. Such refrigeration units often comprise thermal electric devices or refrigerated baths. These cooling devices can cause condensate to form in humid conditions on the cooled parts, such as a pump head. In many instances, the cooling devices are remote from the pump, so that the tubing between the cooling devices and the pump can form condensate. This condensate causes water drippage everywhere within cooling components, requiring huge drip trays. Condensate collection trays often succumb to bacterial growth due to long periods of standing water in trays. In addition, often the refrigerated CO2 fluid is mixed with a solvent, generally methanol (or MEOH), which is at room temperature. When solvents at greatly different temperatures mix, thermal non-equilibrium effects may induce thermal errors that adversely affect separations. Additionally, pressure sensors in the pumps may overcompensate or under compensate for operating pressure, because of large temperature changes in the CO2 and subsequent exposure of the CO2 temperature to the pressure sensor. Other electro-mechanical devices can be sensitive to cooling temperatures and operate undesirably.